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Water Slurry <br /> At the option of the Contractor,water may be used as slurry when casing is used for the entire length of the drilled hole. <br /> Water slurry shall be tested for conformance to the requirements shown in the following table: <br /> WATER SLURRY <br /> PROPERTY REQUIREMENT TEST <br /> Density(kg/m3) <br /> Mud Weight <br /> -prior to final (Density) <br /> cleaning 1017* API 13B-1 <br /> -just prior to Section 1 <br /> placing concrete <br /> Sand Content <br /> (percent) Sand <br /> API 13B-1 <br /> -prior to final less than or equal to Section 5 <br /> cleaning 0.5 <br /> just prior to placing <br /> concrete <br /> *When approved by the Engineer, salt water slurry may be used, <br /> and the allowable densities may be increased up to 32 kg/m3. <br /> Construction <br /> The Contractor shall submit a placing plan to the Engineer for approval prior to producing the test batch for cast-in- <br /> drilled-hole concrete piling and at least 10 working days prior to constructing piling. The plan shall include complete <br /> descriptions,details,and supporting calculations as listed below: <br /> A. Requirements for all cast-in-drilled hole concrete piling: <br /> 1. Concrete mix design,certified test data,and trial batch reports. <br /> 2. Drilling or coring methods and equipment. <br /> 3. Proposed method for casing installation and removal when necessary. <br /> 4. Plan view drawing of pile showing reinforcement and inspection pipes,if required. <br /> 5. Methods for placing,positioning,and supporting bar reinforcement. <br /> 6. Methods and equipment for accurately determining the depth of concrete and actual and theoretical volume <br /> placed,including effects on volume of concrete when any casings are withdrawn. <br /> 7. Methods and equipment for verifying that the bottom of the drilled hole is clean prior to placing concrete. <br /> 8. Methods and equipment for preventing upward movement of reinforcement, including the Contractor's means <br /> of detecting and measuring upward movement during concrete placement operations. <br /> B. Additional requirements when concrete is placed under slurry: <br /> 1. Concrete batching, delivery, and placing systems, including time schedules and capacities therefor. Time <br /> schedules shall include the time required for each concrete placing operation at each pile. <br /> 2. Concrete placing rate calculations. When requested by the Engineer, calculations shall be based on the initial <br /> pump pressures or static head on the concrete and losses throughout the placing system, including anticipated <br /> head of slurry and concrete to be displaced. <br /> 3. Suppliers' test reports on the physical and chemical properties of the slurry and any proposed slurry chemical <br /> additives,including Material Safety Data Sheet. <br /> 4. Slurry testing equipment and procedures. <br /> 5. Methods of removal and disposal of excavation,slurry,and contaminated concrete,including removal rates. <br /> 6. Methods and equipment for slurry agitating,recirculating,and cleaning. <br /> In addition to compressive strength requirements, the consistency of the concrete to be deposited under slurry shall be <br /> verified before use by producing a test batch. The test batch shall be produced and delivered to the project under conditions <br /> and in time periods similar to those expected during the placement of concrete in the piles. Concrete for the test batch shall <br /> be placed in an excavated hole or suitable container of adequate size to allow for testing as specified herein. Depositing of <br /> Contract No. 10-OM7104 <br /> 164 <br />